Centrifugal governor for a carburetor



June 20, 1967 E. c. PELZ, JR 3,326,195

CENTRIFUGAL GOVERNOR FOR A CARBURETOR Filed Oct. 1, 1965 2 Sheets-Sheet 1 INVENTOR EDWARD CPELZ,JR

A TORNEY June 20, 1967 c, PELZ' JR 3,326,195

CENTRIFUGAL GOVERNOR FOR A CARBURETOR Filed Oct. 1, 1965 2 Sheets-Sheet P,

INVENTOR EDWARD C. PELZ,JR.

United States Patent 3,326,195 CENTRIFUGAL GGVERNOR FQR A CARIIURETOR Edward C. Pelz, .Ir., Grabiil, Ind, assignor to International Harvester Company, a corporation of Delaware Fiied Oct. 1, 1965, Ser. No. 492,012 Claims. (Cl. 123103) The present invention relates to a governing mechanism for use on an internal combustion engine and more particularly to a vacuum controlled engine governor which cooperates with the carburetor of an engine to limit the speed of the engine.

Governors are commonly used on truck, tract-or, marine and stationary engines to avoid or limit excessive speeds, and can be classified as either mechanical, velocity or vacuum governors. The present invention relates to a simplified type of vacuum governor operated by centrifugal force. A curved rubber blade is positioned within and rotated with a housing and cooperates with an opening in the housing side wall to limit air flow through the governor which will in turn actuate a diaphragm controlling opening and closing of a throttle plate in the carburetor.

Among the objects of the present invention is the provision of a governor for an internal combustion. engine cooperating with a carburetor where the vacuum created in the carburetor causes an air flow through the governor. Reduction in the air flow in the governor causes build-up of the vacuum in the carburetor which acts to close the throttle plate, thus limiting the speed of the engine controlled by the carburetor.

Another object of the present invention is the provision of a centrifugal governor which is rotated by a shaft connected to the engine for rotation therewith. The governor includes a body having a shaft rotatably mounted therein and an enlarged chamber in the body at the free end of the shaft. An air inlet in the body communicates with the shaft and a passage therethrough and an air outlet communicates with the enlarged chamber. A housing or cap is connected onto the end of the shaft to rotate therewith and contains a flexible member to control air flow from the inlet through the shaft and out of the housing through an opening in the wall thereof.

A further object of the present invention is the provision of a centrifugal governor having a rotating resilient member secured to the rotating shaft with one or more outwardly curved resilient arms which do not contact the walls of the housing on the shaft when the member is stationary but, as the speed of rotation of the shaft, housing and resilient member increases, the arms or blades fan out to contact the wall of the housing until at a predetermined speed one arm covers and seals the opening in the housing to shut off air fiow through the governor.

The present invention also comprehends the provision of a centrifugal governor where the housing is adjustable relative to the curved arms of the resilient member. Rotation of the housing relative to the resilient member will cause a change of location of the air flow opening in the housing relative to the resilient arms which alters the governing speed of the unit.

A- further object of the present invention is the provision of a centrifugal governor which is simple in construction, economical to manufacture and eflicient in operation.

Additional objects and advantages of my invention should be apparent to those skilled in the art from the following description when considered in connection with the accompanying drawings illustrating a preferred embodiment thereof, wherein FIGURE 1 is a front elevational view partially in ver- "ice tical cross section illustrating the governor as it is applied to a carburetor for an internal combustion engine.

FIG. 2 is an enlarged cross sectional view of the centrifugal governor in its housing.

FIG. 3 is a vertical cross sectional view taken on the irregular line 33 of FIG. 2 showing the structure of the flexible rotary member.

FIG. 4 is a partial vertical cross sectional view similar to FIG. 2, but showing a tool inserted for adjustment of of the governor.

FIG. 5 is a top plan view of the governor and adjustment tool of FIG. 4.

FIG. 6 is a perspective view of the cap or housing for the governor.

Referring more particularly to the drawings wherein is shown an illustrative embodiment of the present invention, FIG. 1 discloses a centrifugal governor 10 connected to a carburetor 11 by an air intake line 12 and an air exhaust line 13. The carburetor 11 includes an air intake 14 for a barrel 15 having a restriction or venturi throat 16, and a conventionally operated throttle plate 17 is mounted on a shaft 18 below the restriction 16.

The shaft 18 is rotatably mounted in the carburetor 11 and extends at one end through a recess 19 in an assembly 21 at one side of the carburetor barrel 15. An anti-friction bearing 22 supports the shaft 18, and a spring 23 encompasses the shaft 18 in recess 19 and biases the bearing 22 to the left as shown in FIG. 1. The outer end of shaft 18 is secured to one end of an elongated lever assembly 24 with the opposite end of the lever assembly connected to a vertical shaft 25, and an expansion spring 26 is connected at one end to a rod 27 and at the opposite end to a rod 28 on the lever assembly 24; the spring 26 yieldably biasing the lever assembly 24 and the throttle plate 17 to its open position as shown in FIG. 1.

The assembly 21 includes a housing 21 with a recess 31 for the lever assembly 24 and expansion spring 26 and an upwardly opening recess 32 above the recess 31 for a diaphragm 33 having its outer periphery clamped between the other edge 34 defining the recess 32 and the outer edge of a cap or cover 35 secured to the body or housing 29 by suitable securing means such as the screws or bolts 36. The recess 31 is also closed by a cover 37 secured by screws or bolts 38. The vertical shaft 25 connected at its lower end to the lever assembly 24 is connected at its upper end to the center of the diaphragm 33 by diaphragm disks or washers 39.

The barrel 15 of the carburetor 11 has an inclined or slanted intake passage 41 adjacent the upper open end air intake 14 communicating with a fitting 42 connected to the air intake line 12 to the governor 10. The air exhaust or return line 13 is connected to a fitting 43 in the body 29 below the recess 32 and communicates with a hori zontal passage 44. A generally upwardly inclined passageway 45 extends from the chamber 46 above the diaphragm 33 in the cover 35 to a junction with and downwardly past the horizontal passage 44 to a generally vertical passage 47 which communicates with a pair of parallel spaced upper and lower horizontal passages 48 and 49, respectively.

The upper passage 48 extends to and opens into the carburetor 11 at the restriction 16, and the lower passage 49 opens into the barrel 1-5 at a point 51 below the throttle plate 17. As is well known, the restriction 16 creates a reduced pressure thereat and the pressure at the point 51 is higher than at the restriction 16 but reduced below the air pressure at the air intake 14. The reduced pressure at the restriction 16 and the point 51 tends to draw air into the carburetor from the passages 48 and 49. If there is freedom of air flow through the governor 10, then air passes through the intake passage 41, line 12, governor 10, line 13, and passages 44 and 46 to the passages 48 and 49 and into the carburetor.

The governor 10 includes an elongated generally cylindrical body 52 having a central axially extending passage 53 terminating at one end in an enlarged chamber 54; the open end of which is closed by a cap 55. The other end of the passage 53 is open to receive a rotary shaft 56 having a gear 57 at its outer end outside the body 52 to be driven by a suitable gear and drive connection 58 from the engine. The shaft 56 extends through the axial passage 53 and terminates in the enlarged chamber 54 in a knurled or ribbed end 59.

A fitting 61 in the body 52 connects the air intake line 12 to a passage 62 which extends to the axial passage 53. The shaft 56 has an annular groove 63 aligned with the inner end of passage 62 and a diametrically extending passage 64 in the shaft 56 communicates between the groove 63 and an axial passage 65 extending through the shaft to and opening at the knurled end thereof. A fitting 66 in the body 52 communicates between the air exhaust line 13 and the enlarged chamber 54.

A rotary member 67 is formed of a flexible resilient material, such as rubber or plastic, and includes an enlarged hub 68 having a central recess or opening 6? receiving the knurled end 59 of shaft 56 to rotate therewith. A projection 71 has outwardly curved blades or vanes 72 and is connected to the hub 68 through a central portion or neck 73 having radially extending passages 74 from an axial passage '75 communicating with the recess 69 and the open end of passage 65 in the shaft 56. A hollow housing or cap 76 is carried by said rotary member and formed with an open end 77 to encompass and sealingly engage the outer periphery of the enlarged hub 68 of the member 67. The housing or cap includes a small opening 78 in the side wall thereof and aligned laterally with the blades or vanes 72. The opening 78 allows for the passage of air through the governor from the radial passages '74 to the fitting 66.

Also shown in the wall of the cap 76 is a larger opening 79 which is aligned with a somewhat larger recess 81 in the periphery of the hub 68 for a tool 82 (FIGS. 4 and 5) for adjustment of the governor. The tool 82 includes a circular disk 83 and an eccentricaliy mounted shaft $4 secured to and extending through the disk 83 and provided with a bent upper end 85 forming a handle. The projecting end 86 of the shaft is received in a complementary recess in the hub 68 and extends below the recess 81. The disk 83 is received in the recess 81 and complementarily received in the opening '79 in the cap. Rotation of the shaft 84 by the bent end or handle 85 causes rotation of the disk about the eccentrically mounted shaft; the disk 83 engaging the confining edges of opening 79 and causing rotation of the cap 76 relative to the hub 68 and movement of the small opening 78 relative to the facing blade or vane 72. The tool 82 is inserted through a threaded opening 87 in the housing 52 to engage the opening 79 in the cap 76; the opening 87 normally being sealed by a removable threaded plug 83 (FIGS. 1 and 2) during operation of the engine and governor 10.

The governor 1G is shown in its normal position in FIGS. 2 and 3 when the shaft 56 is not rotating. When the engine is operating, downward movement of the pistons causes a vacuum which draws air through the carburetor 11, and air flow passes through the governor by means of the intake line 12, fitting 61, passage 62, annular groove 63, passages 64 and 65 in shaft 56, passsages 74 and 75 in resilient member 67, opening 78 in cap 76, fitting 66 and exhaust line 13 due to the pressure drop created at the restriction 16 and the point 51. As the motor operates, the shaft 56 is rotated and rotates the member 67 and cap 7 6.

As the speed of rotation of the shaft 56 increases, the blades or vanes 72 begin to fan out with the tips of the blades engaging the interior surface of the cap 76 and progressively more of the blade engaging the cap as speed of rotation increases. The fanning out of the blades 72 inhibits the passage of air through the opening 78 until a predetermined speed is reached when the opening 78 is sealed by one of the blades. As the passage of air is inhibited in the governor 10, the vacuum created in the carburetor draws the air from the chamber 46 above the diaphragm 33 through the slanting passageway 45 creating a partial vacuum above the diaphragm. As the vacuum increases, the diaphragm is drawn upward thus rotating the lever assembly 21 and shaft 18 against the action of the spring 26 to close the throttle plate 17, whereby when the opening 7 3 in the governor is closed, the throttle plate 17 is closed by the diaphragm to govern the speed of the engine.

By adjusting the cap '76 relative to the rotary member 67, the opening 78 in the cap is moved closer to or farther away from the tip of the blade 72 on the rotary member to adjust the speed at which the blade 72 closes the opening 7 3. This adjustment provides a wide range of governing ability.

Having disclosed the invention, 1 claim:

1. A centrifugal governor for the carburetor of an internal combustion engine, comprising a governor body having a chamber adjacent one end, a shaft rotatably mounted in said body and having one end terminating in said chamber, drive means to rotate said shaft, a cap connected to said end of the shaft within said chamber and partially enclosing a space within said chamber, said cap having an opening in the sidewall thereof providing fluid communication between said space and said chamber, said shaft having a central passage extending from a point in said body to and opening into said space, an air inlet communicating with said point in the housing and an air outlet communicating with said chamber, and flexible means in said space and having one end rigidly secured to said shaft and adapted to rotate with said cap and shaft, said flexible means including a portion movable into engagement with said cap to seal the opening in the cap at a predetermined speed of rotation.

2. A centrifugal governor as set forth in claim 1, in which said shaft rotates at a speed related to the speed of rotation of said internal combustion engine.

3. A centrifugal governor as set forth in claim 1, in which said flexible means include a resilient member having at least one curved flexible arm which normally does not engage the walls of the cap but expands outward to progressively engage the cap as the speed of rotation increases.

4. A centrifugal governor as set forth in claim 1, including adjustment means to adjust the angular position of the opening in the cap relative to said flexible means.

5. A centrifugal governor for the carburetor of an internal combustion engine having a throttle plate therein, comprising a cylindrical body having a chamber adjacent one end, a shaft rotatably mounted within said body having one end terminating within said chamber and the opposite end extending beyond said body, drive means on said opposite end operatively connected to the engine to rotate said shaft, a cylindrical housing connected to the end of the shaft within said chamber for rotation therewith, said housing having an opening in the sidewall thereof, said shaft having an axially extending passage from a point intermediate the ends of the shaft to and opening into said housing, an air inlet communicating with the end of the passage intermediate the ends of the shaft and an air outlet communicating with said chamber, and a flexible member positioned within said housing and including a hub secured to the end of the shaft for rotation therewith and plural outwardly extending curved blades which normally do not Contact said housing but upon rotation expand outwardly to gradually engage the interior wall of the housing and as the speed of rotation is increased one of the blades closes the opening therein.

6. A centrifugal governor as set forth in claim 5, in

which said air inlet and air outlet are connected to the carburetor of the engine to control the throttle plate thereof.

7. A centrifugal governor as set forth in claim 5, in which said shaft has one or more radial passages at the one end of said axial passage intermediate the ends and an annular groove encompassing the shaft and communicating with the radial passages and said air inlet.

8. A centrifugal governor as set forth in claim 5, in which said hub of the flexible member sealingly engages and carries said housing upon rotation of the shaft, said hub being separated from said blades by a neck of reduced diameter having an axial pass-age aligned with the passage in the shaft and radial passages opening into the housing.

9. A centrifugal governor as set forth in claim 8, including means for adjusting said housing relative to said blades.

10. A centrifugal governor as set forth in claim 8, in which said hub has a recess in the periphery thereof with an offset deeper recess, said housing having an opening generally aligned with the recess in the hub, and said body having an opening in the chamber wall for receiving a circular adjustment member with an offset shaft for adjusting the housing and air opening relative to said hub and flexible blades.

References Cited UNITED STATES PATENTS 3/1951 Mallory 123-103 9/1959 Panhard l37-56 X 

1. A CENTRIFUGAL GOVERNOR FOR THE CARBURETOR OF AN INTERNAL COMBUSTION ENGINE, COMPRISING A GOVERNOR BODY HAVING A CHAMBER ADJACENT ONE END, A SHAFT ROTATABLY MOUNTED IN SAID BODY AND HAVING ONE END TERMINATING IN SAID CHAMBER, DRIVE MEANS TO ROTATE SAID SHAFT, A CAP CONNECTED TO SAID END OF THE SHAFT WITHIN SAID CHAMBER AND PARTIALLY ENCLOSING A SPACE WITHIN SAID CHAMBER, SAID CAP HAVING AN OPENING IN THE SIDEWALL THEREOF PROVIDING FLUID COMMUNICATION BETWEEN SAID SPACE AND SAID CHAMBER, SAID SHAFT HAVING A CENTRAL PASSAGE EXTENDING FROM A POINT IN SAID BODY TO AND OPENING INTO SAID SPACE, AN AIR INLET COMMUNICATING WITH SAID POINT IN THE HOUSING 